         letter->number (zipmap "abcdefg" (range 8))
         number->letter (zipmap (range 8) "ABCDEFG")
         base-number    (->> pitch name first letter->number)
-        base-notes     (take 7 (map number->letter 
+        base-notes     (take 7 (map number->letter
                                     (iterate #(rem (inc %) 7) base-number)))
         {:keys [sharps flats]} (key-signature pitch major-or-minor)]
-    (map (fn [letter] 
-           (str letter (when (and sharps (sharps letter)) \#) 
+    (map (fn [letter]
+           (str letter (when (and sharps (sharps letter)) \#)
                        (when (and flats (flats letter)) \b)))
          base-notes)))
 


(defn- circle-of-fifths [major-or-minor]
  (zipmap (case major-or-minor
            :major [:c-flat :g-flat :d-flat :a-flat :e-flat :b-flat :f 
                    :c :g :d :a :e :b :f-sharp :c-sharp]
            :minor [:a-flat :e-flat :b-flat :f :c :g :d
                    :a :e :b :f-sharp :c-sharp :g-sharp :d-sharp :a-sharp]) 
          (range -7 8)))

(defn key-signature [pitch major-or-minor]

(defmethod notes :blues [{:keys [pitch]}]
  (let [minor-pentatonic (pentatonic-scale pitch :minor)
        extra-note       (augment (nth minor-pentatonic 2))]
    (set (concat (take 3 minor-pentatonic)
                 [extra-note]
                 (drop 3 minor-pentatonic)))))
